1. Field
Aspects of exemplary embodiments described herein relate to a communication interface device and a display device, and more specifically, to a communication interface device which can determine whether an image signal is input with a simple circuit and a display device.
2. Description of the Related Art
A display device is a device which processes and displays digital or analog video signals that are received from an external source or various video signals stored in an internal storage device as compressed files. In this case, the digital or analog video signals that are received from the external source may be broadcasting signals, digital satellite broadcasting signals, or signals that are transmitted from various kinds of external devices (e.g., a set-top box, a disk player, a mobile device, and a PC) or servers based on Internet protocols.
In order to save power, such a display device is in a power-saving state when a video signal is not input, and converts the input video signal into an operation state when a video signal is input, thereby displaying an image corresponding to the input video signal. For this operation, a circuit for determining whether a video signal is input through the input/output terminal is required.
There are cases that a recent display device uses a differential signaling to transmit an image signal. Herein, the differential signaling is the technology of pairing a single signal and a signal having a phase opposite to a phase of the signal and transmitting the pair.
Conventionally, a circuit for converting a differential signal to a single signal for determining an input of a differential signal transmitted as such a differential signaling and a circuit for determining whether an image signal is input based on the output signal of a single circuit are necessary.
Because a complicated circuit for detecting whether a differential signal is input is necessary, a method which can check an input of a differential signal with a simple circuit is demanded.